I received this Marlin 336 RC on a trade and while trying to find values and dates I noticed that I haven't seen any other similar guns with this brass screw in the reciever. While tearing down for a complete cleaning I noticed this screw seems to have no function at all.. Do any of you have any idea what it was for? Is it a factory screw? Any help would be greatly appreciated.

Could that be a plug screw replacing a saddle ring stud?

I've been doing a lot of research and apparently that's exactly what it is. Apparently this is the "texan" model and someone decided in the last 40 years to remove the ring. DANG IT!!!!!

There are replacements out there if you have time to look. Good luck!

Ive been looking. They are hard to find. LOL.

Maybe a '94 Win ring will work if you can't find a Marlin. The Marlin ring was brass, but you could have a steel one plated if the stud screw would work. Tech support at Dixie might be able to provide the threaded stud size and length for these:
http://www.dixiegunworks.com/advanc...mp;keywords=saddle+ring&x=10&y=8

Also e bay has some every once an a while

I wonder if the threads are the same on the Marlin and Winchesters?

This place makes them to fit Winchesters.
I would imagine if he had your screw or the measurements from it, he could answer your question

With the correct tap it may be possible to make it it fit if it's different

http://www.tapaderaswinchesters.com/saddlerings.html